FindFirstPrinterChangeNotification function

05/31/2018

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The FindFirstPrinterChangeNotification function creates a change notification object and returns a handle to the object. You can then use this handle in a call to one of the wait functions to monitor changes to the printer or print server.

The FindFirstPrinterChangeNotification call specifies the type of changes to be monitored. You can specify a set of conditions to monitor for changes, a set of printer information fields to monitor, or both.

A wait operation on the change notification handle succeeds when one of the specified changes occurs in the specified printer or print server. You then call the FindNextPrinterChangeNotification function to retrieve information about the change, and to reset the change notification object for use in the next wait operation.

Syntax

Parameters

hPrinter [in]

A handle to the printer or print server that you want to monitor. Use the OpenPrinter or AddPrinter function to retrieve a printer handle.

fdwFilter

The conditions that will cause the change notification object to enter a signaled state. A change notification occurs when one or more of the specified conditions are met. The fdwFilter parameter can be zero if pPrinterNotifyOptions is non-NULL.

This parameter can be one or more of the following values.

Value

Meaning

PRINTER_CHANGE_FORM

Notify of any changes to a form. You can set this general flag or one or more of the following specific flags:

PRINTER_CHANGE_ADD_FORM

PRINTER_CHANGE_SET_FORM

PRINTER_CHANGE_DELETE_FORM

PRINTER_CHANGE_JOB

Notify of any changes to a job. You can set this general flag or one or more of the following specific flags:

PRINTER_CHANGE_ADD_JOB

PRINTER_CHANGE_SET_JOB

PRINTER_CHANGE_DELETE_JOB

PRINTER_CHANGE_WRITE_JOB

PRINTER_CHANGE_PORT

Notify of any changes to a port. You can set this general flag or one or more of the following specific flags:

PRINTER_CHANGE_ADD_PORT

PRINTER_CHANGE_CONFIGURE_PORT

PRINTER_CHANGE_DELETE_PORT

PRINTER_CHANGE_PRINT_PROCESSOR

Notify of any changes to a print processor. You can set this general flag or one or more of the following specific flags:

PRINTER_CHANGE_ADD_PRINT_PROCESSOR

PRINTER_CHANGE_DELETE_PRINT_PROCESSOR

PRINTER_CHANGE_PRINTER

Notify of any changes to a printer. You can set this general flag or one or more of the following specific flags:

PRINTER_CHANGE_ADD_PRINTER

PRINTER_CHANGE_SET_PRINTER

PRINTER_CHANGE_DELETE_PRINTER

PRINTER_CHANGE_FAILED_CONNECTION_PRINTER

PRINTER_CHANGE_PRINTER_DRIVER

Notify of any changes to a printer driver. You can set this general flag or one or more of the following specific flags:

PRINTER_CHANGE_ADD_PRINTER_DRIVER

PRINTER_CHANGE_SET_PRINTER_DRIVER

PRINTER_CHANGE_DELETE_PRINTER_DRIVER

PRINTER_CHANGE_ALL

Notify if any of the preceding changes occur.

PRINTER_CHANGE_SERVER

Windows 7: Notify of any changes to the server. This flag is not included in the changes monitored by setting the PRINTER_CHANGE_ALL value.

When this flag is set to zero (0), FindFirstPrinterChangeNotification will only work for 2D printers. This is the default value.

pPrinterNotifyOptions [in, optional]

A pointer to a PRINTER_NOTIFY_OPTIONS structure. The pTypes member of this structure is an array of one or more PRINTER_NOTIFY_OPTIONS_TYPE structures, each of which specifies a printer information field to monitor. A change notification occurs when one or more of the specified fields changes. When a change occurs, the FindNextPrinterChangeNotification function can retrieve the new printer information. This parameter can be NULL if fdwFilter is nonzero.

Return value

If the function succeeds, the return value is a handle to a change notification object associated with the specified printer or print server.

If the function fails, the return value is INVALID_HANDLE_VALUE.

Remarks

Note

This is a blocking or synchronous function and might not return immediately. How quickly this function returns depends on run-time factors such as network status, print server configuration, and printer driver implementation factors that are difficult to predict when writing an application. Calling this function from a thread that manages interaction with the user interface could make the application appear to be unresponsive.

To monitor a printer or print server, call the FindFirstPrinterChangeNotification function, then use the returned change notification object handle in a call to one of the wait functions. A wait operation on a change notification object is satisfied when the change notification object enters the signaled state. The system signals the object when one or more of the changes specified by fdwFilter or pPrinterNotifyOptions occurs in the monitored printer or print server.

When you call FindFirstPrinterChangeNotification, either fdwFilter must be nonzero or pPrinterNotifyOptions must be non-NULL. If both are specified, notifications will occur for both.

When a wait operation on a printer change notification object is satisfied, call the FindNextPrinterChangeNotification function to determine the cause of the notification. For a condition specified by fdwFilter, FindNextPrinterChangeNotification reports the condition or conditions that changed. For a printer information field specified by pPrinterNotifyOptions, FindNextPrinterChangeNotification reports the field or fields that changed as well as the new information for these fields. FindNextPrinterChangeNotification also resets the change notification object to the nonsignaled state so you can use it in another wait operation to continue monitoring the printer or print server.

With one exception, do not call the FindNextPrinterChangeNotification function if the change notification object is not in the signaled state. If the wait function returns the value WAIT_TIMEOUT, the change object is not in the signaled state. Call the FindNextPrinterChangeNotification function only if the wait function succeeds without timing out. The exception is when FindNextPrinterChangeNotification is called with the PRINTER_NOTIFY_OPTIONS_REFRESH bit set in the pPrinterNotifyOptions parameter.

Callers of FindFirstPrinterChangeNotification must ensure that the printer handle passed into FindFirstPrinterChangeNotification remains valid until FindClosePrinterChangeNotification is called. If the printer handle is closed before the printer change notification handle, further notifications will fail to be delivered.

FindFirstPrinterChangeNotification will not send change notifications for 3D printers to server handles.

Note

In Windows XP with Service Pack 2 (SP2) and later, the Internet Connection Firewall (ICF) blocks printer ports by default, but an exception for File and Print Sharing can be enabled. If a user makes a printer connection to another machine, and the exception is not enabled, then the user will not receive printer change notifications from the server. A machine admin will have to enable exception.